source: branches/Persistence Test/WinFormsUI/Docking/NestedPaneCollection.cs @ 4593

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Drawing;

namespace WeifenLuo.WinFormsUI.Docking
{
  public sealed class NestedPaneCollection : ReadOnlyCollection<DockPane>
  {
    private INestedPanesContainer m_container;
    private VisibleNestedPaneCollection m_visibleNestedPanes;

    internal NestedPaneCollection(INestedPanesContainer container)
            : base(new List<DockPane>())
    {
      m_container = container;
      m_visibleNestedPanes = new VisibleNestedPaneCollection(this);
    }

    public INestedPanesContainer Container
    {
      get { return m_container; }
    }
    
    public VisibleNestedPaneCollection VisibleNestedPanes
    {
      get { return m_visibleNestedPanes;  }
    }

    public DockState DockState
    {
      get { return Container.DockState; }
    }

    public bool IsFloat
    {
      get { return DockState == DockState.Float;  }
    }

    internal void Add(DockPane pane)
    {
      if (pane == null)
        return;

      NestedPaneCollection oldNestedPanes = (pane.NestedPanesContainer == null) ? null : pane.NestedPanesContainer.NestedPanes;
      if (oldNestedPanes != null)
        oldNestedPanes.InternalRemove(pane);
      Items.Add(pane);
      if (oldNestedPanes != null)
        oldNestedPanes.CheckFloatWindowDispose();
    }

    private void CheckFloatWindowDispose()
    {
      if (Count == 0 && Container.DockState == DockState.Float)
      {
        FloatWindow floatWindow = (FloatWindow)Container;
        if (!floatWindow.Disposing && !floatWindow.IsDisposed)
          NativeMethods.PostMessage(((FloatWindow)Container).Handle, FloatWindow.WM_CHECKDISPOSE, 0, 0);
      }
    }

    internal void Remove(DockPane pane)
    {
      InternalRemove(pane);
      CheckFloatWindowDispose();
    }

    private void InternalRemove(DockPane pane)
    {
      if (!Contains(pane))
        return;

      NestedDockingStatus statusPane = pane.NestedDockingStatus;
      DockPane lastNestedPane = null;
      for (int i=Count - 1; i> IndexOf(pane); i--)
      {
        if (this[i].NestedDockingStatus.PreviousPane == pane)
        {
          lastNestedPane = this[i];
          break;
        }
      }

      if (lastNestedPane != null)
      {
        int indexLastNestedPane = IndexOf(lastNestedPane);
        Items.Remove(lastNestedPane);
        Items[IndexOf(pane)] = lastNestedPane;
        NestedDockingStatus lastNestedDock = lastNestedPane.NestedDockingStatus;
        lastNestedDock.SetStatus(this, statusPane.PreviousPane, statusPane.Alignment, statusPane.Proportion);
        for (int i=indexLastNestedPane - 1; i>IndexOf(lastNestedPane); i--)
        {
          NestedDockingStatus status = this[i].NestedDockingStatus;
          if (status.PreviousPane == pane)
            status.SetStatus(this, lastNestedPane, status.Alignment, status.Proportion);
        }
      }
      else
        Items.Remove(pane);

      statusPane.SetStatus(null, null, DockAlignment.Left, 0.5);
      statusPane.SetDisplayingStatus(false, null, DockAlignment.Left, 0.5);
      statusPane.SetDisplayingBounds(Rectangle.Empty, Rectangle.Empty, Rectangle.Empty);
    }

    public DockPane GetDefaultPreviousPane(DockPane pane)
    {
      for (int i=Count-1; i>=0; i--)
        if (this[i] != pane)
          return this[i];

      return null;
    }
  }
}